The invention concerns a method and a device for determining the filling level and can be applied, in particular, for the ascertainment of the simmering process of mineral oil products.
When determining the simmering process of mineral oil products, a certain sample amount is heated in a distillation flask under pre-specified conditions and condensed again via a cooling tube. The condensed volume is retained in a measuring cylinder and the dependency of the volume increase to the temperature prevailing in the distillation flask in each case is ascertained.
The presentation of the temperature to the retained liquid volume provides conclusions with regard to the composition and usability of the distilled material and is internationally standardized. In particular, it is used in refineries for the purpose of inspecting fuels.
This distillation test process was originally performed manually; at the present time, appropriate automatic devices are predominantly used in order to save time. Normally, in such cases, the surface of the liquid to be retained in the measuring cylinder is ascertained in its level by way of a following light barrier, and is thus indicated as a volume. This involves a solution where the light barrier, motor-driven, follows in a controlled manner the continually rising liquid level.
A disadvantage with the known solutions is the fact that the applied mechanical system is sophisticated, particularly because of the moving parts in the manufacture and maintenance, and is susceptible to disturbances during operation.
For this reason, the invention is based on the task assignment of creating a method and a device which make possible the realization of an inexpensively manufacturable and reliably functioning measuring arrangement without the use of moving parts.
This task assignment is solved by the features in the claims 1, 3, 6 and 7. Purposeful embodiments of the invention are contained in the Subclaims.
A significant advantage of the invention lies in the fact that no moving parts are required for determining the filling level. This is realized in such a way that by means of at least two stationary sensors, a first filling level (level 1) and at least a second filling level (level 2) are defined and the number of drops required for reaching level 1 and level 2 is recorded, by way of a further sensor the number of drops dropped in during the simmering process is counted and, by way of calculation, the additional partial volume and the filling level is determined, or by means of the stationary sensors the first filling level (level 1) and at least the second filling level (level 2) are defined and the weight required for reaching level 1 and level 2 is recorded, the additional weight in the simmering process is measured and, again by means of calculation, the additional partial volume and the filling gauge level is determined.
A device which is inexpensive to manufacture, easy to operate and convenient to maintain is realized in such a way that, for the purpose of level recording in a measuring cylinder in a measuring arrangement a first stationary measuring sensor and at least a second stationary measuring sensor as well as a metering sensor is arranged, where the positions of the measuring sensors represent a defined relation to the filling gauge level in the measuring cylinder and the metering sensor records the number of drops dropped in during the simmering process. In like manner it is also possible to record the additional weight instead of drop counting where, for level recording in the measuring cylinder in the measuring arrangement, again a first stationary sensor and at least a second stationary sensor is arranged and the positions of the sensors represent a defined relation to the filling level in the measuring cylinder and the measuring cylinder is connected with means for recording the weight.